Nagarajan Vembu

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The title mol-ecule, C(21)H(18)O(8), crystallizes in two crystal polymorphs, see also Nallasivam, Nethaji, Vembu & Jaswant [Acta Cryst. (2009), E65, o312-o313]. The main difference between the two polymorphs is in the conformation of the oxomethyl-acetate groups with regard to the almost planar [total puckering amplitude 0.047 (2) Å] chromene ring. In the(More)
Reported is the synthesis of azo mutual prodrugs of the nonsteroidal anti-inflammatory agents (NSAIDs) 4-aminophenylacetic acid (4-APAA) or 5-aminosalicylic acid (5-ASA) with peptides, including an antibiotic peptide temporin analogue modified at the amino terminal by an α-aminoisobutyric acid (Aib) residue. These prodrugs are designed for colonic delivery(More)
The indole and phenyl ring systems in the title compound, C(18)H(18)N(2)S(2), are nearly coplanar, the indole and phenyl planes forming a dihedral angle of 6.5 (1)°. Supra-molecular aggregation is effected by N-H⋯S, C-H⋯S, N-H⋯π and C-H⋯π inter-actions. The crystal studied exhibited inversion twinning.
There are two independent formula units in the asymmetric unit of the title compound, C(4)H(10)NO(+)·C(6)H(2)N(3)O(7) (-). The morpholinium cations in both mol-ecules are puckered and adopt a chair conformation. Intermolecular N-H⋯O and C-H⋯O inter-actions generate rings of motifs R(2) (1)(5) and R(1) (2)(6). The supra-molecular aggregation is completed by(More)
In the title compound, C(29)H(22)O(4), the chromene ring is almost planar with a small puckering [0.143 (2) Å]. The crystal structure is stabilized by C-H⋯O and C-H⋯π inter-actions. Edge-to-face (centroid-centroid distances of 3.894 and 3.673 Å) and face-to-face (centroid-centroid distance of 3.460 Å) π-π-ring electron inter-actions are also observed.
In 2-chlorophenyl 3-nitrobenzenesulfonate, C(12)H(8)ClNO(5)S, and 2,4-dichlorophenyl 3-nitrobenzenesulfonate, C(12)H(7)Cl(2)NO(5)S, weak C-H...O interactions generate S(5), S(6) and R(2)(2)(7) rings. The supramolecular aggregation is completed by the presence of pi-pi interactions and intermolecular van der Waals short contacts.
The 1,3-benzodioxole ring systems in the title compound, C(22)H(22)O(8), are almost planar. The perhydro-furofuranyl system linking them adopts a distorted double-envelope conformation. Supra-molecular aggregation is effected by C-H⋯O, C-H⋯π and π-π [centroid-centroid distance of 3.755 Å, inter-planar distance of 3.633 Å and dihedral angle of 14.6°](More)